//
//  ConfigFile.hpp
//  MNN
//
//  Created by MNN on 2019/01/22.
//  Copyright © 2018, Alibaba Group Holding Limited
//

#ifndef CONFIGFILE_HPP
#define CONFIGFILE_HPP

#include <fstream>
#include <iostream>
#include <vector>
#include <map>
#include <sstream>
#include <string>

/*
* \brief Generic configuration Class
* can deal with the file like below:
*
*           input_size = 1
*           input_names = ImageTensor
*           input_dims = 1x3x320x180
*           output_size = 1
*           output_names = strided_slice_61
*
*/
class ConfigFile {
    // Data
protected:
    std::string m_Delimiter;                       //!< separator between key and value
    std::string m_Comment;                         //!< separator between value and comments
    std::map<std::string, std::string> m_Contents; //!< extracted keys and values

    typedef std::map<std::string, std::string>::iterator mapi;
    typedef std::map<std::string, std::string>::const_iterator mapci;
    // Methods
public:
    ConfigFile(std::string filename, std::string delimiter = "=", std::string comment = "#");
    ConfigFile() = default;
    template <class T>
    T Read(
        const std::string& in_key) const; //!<Search for key and read value or optional default value, call as read<T>
    template <class T>
    T Read(const std::string& in_key, const T& in_value) const;
    template <class T>
    bool ReadInto(T& out_var, const std::string& in_key) const;
    template <class T>
    bool ReadInto(T& out_var, const std::string& in_key, const T& in_value) const;
    bool FileExist(std::string filename);
    void ReadFile(std::string filename, std::string delimiter = "=", std::string comment = "#");

    // Check whether key exists in configuration
    bool KeyExists(const std::string& in_key) const;

    // Modify keys and values
    template <class T>
    void Add(const std::string& in_key, const T& in_value);
    void Remove(const std::string& in_key);

    // Check or change configuration syntax
    std::string GetDelimiter() const {
        return m_Delimiter;
    }
    std::string GetComment() const {
        return m_Comment;
    }
    std::string SetDelimiter(const std::string& in_s) {
        std::string old = m_Delimiter;
        m_Delimiter     = in_s;
        return old;
    }
    std::string SetComment(const std::string& in_s) {
        std::string old = m_Comment;
        m_Comment       = in_s;
        return old;
    }

    // Write or read configuration
    friend std::ostream& operator<<(std::ostream& os, const ConfigFile& cf);
    friend std::istream& operator>>(std::istream& is, ConfigFile& cf);

protected:
    template <class T>
    static std::string T_as_string(const T& t);
    template <class T>
    static T string_as_T(const std::string& s);
    static void Trim(std::string& inout_s);

    // Exception types
public:
    struct File_not_found {
        std::string filename;
        File_not_found(const std::string& filename_ = std::string()) : filename(filename_) {
        }
    };
    struct Key_not_found { // thrown only by T read(key) variant of read()
        std::string key;
        Key_not_found(const std::string& key_ = std::string()) : key(key_) {
        }
    };
};

/* static */
template <class T>
std::string ConfigFile::T_as_string(const T& t) {
    // Convert from a T to a string
    // Type T must support << operator
    std::ostringstream ost;
    ost << t;
    return ost.str();
}

/* static */
template <class T>
T ConfigFile::string_as_T(const std::string& s) {
    // Convert from a string to a T
    // Type T must support >> operator
    T t;
    std::istringstream ist(s);
    ist >> t;
    return t;
}

/* static */
template <>
inline std::string ConfigFile::string_as_T<std::string>(const std::string& s) {
    // Convert from a string to a string
    // In other words, do nothing
    return s;
}

/* static */
template <>
inline bool ConfigFile::string_as_T<bool>(const std::string& s) {
    // Convert from a string to a bool
    // Interpret "false", "F", "no", "n", "0" as false
    // Interpret "true", "T", "yes", "y", "1", "-1", or anything else as true
    bool b          = true;
    std::string sup = s;
    for (std::string::iterator p = sup.begin(); p != sup.end(); ++p)
        *p = toupper(*p); // make string all caps
    if (sup == std::string("FALSE") || sup == std::string("F") || sup == std::string("NO") || sup == std::string("N") ||
        sup == std::string("0") || sup == std::string("NONE"))
        b = false;
    return b;
}

template <class T>
T ConfigFile::Read(const std::string& key) const {
    // Read the value corresponding to key
    mapci p = m_Contents.find(key);
    if (p == m_Contents.end()) {
        std::cout << "Key Error!" << std::endl;
    }
    return string_as_T<T>(p->second);
}

template <class T>
T ConfigFile::Read(const std::string& key, const T& value) const {
    // Return the value corresponding to key or given default value
    // if key is not found
    mapci p = m_Contents.find(key);
    if (p == m_Contents.end())
        return value;
    return string_as_T<T>(p->second);
}

template <class T>
bool ConfigFile::ReadInto(T& var, const std::string& key) const {
    // Get the value corresponding to key and store in var
    // Return true if key is found
    // Otherwise leave var untouched
    mapci p    = m_Contents.find(key);
    bool found = (p != m_Contents.end());
    if (found)
        var = string_as_T<T>(p->second);
    return found;
}

template <class T>
bool ConfigFile::ReadInto(T& var, const std::string& key, const T& value) const {
    // Get the value corresponding to key and store in var
    // Return true if key is found
    // Otherwise set var to given default
    mapci p    = m_Contents.find(key);
    bool found = (p != m_Contents.end());
    if (found)
        var = string_as_T<T>(p->second);
    else
        var = value;
    return found;
}

template <class T>
void ConfigFile::Add(const std::string& in_key, const T& value) {
    // Add a key with given value
    std::string v   = T_as_string(value);
    std::string key = in_key;
    Trim(key);
    Trim(v);
    m_Contents[key] = v;
    return;
}
std::vector<int> stringToDims(const std::string& str, const std::string& pattern) {
    std::vector<int> res;
    if (str == "") {
        return res;
    }
    std::string strs = str + pattern;
    size_t pos       = strs.find(pattern);

    while (pos != strs.npos) {
        std::string temp = strs.substr(0, pos);
        std::istringstream tempIs(temp);
        int p;
        tempIs >> p;
        res.push_back(p);
        strs = strs.substr(pos + 1, strs.size());
        pos  = strs.find(pattern);
    }

    return res;
}

std::vector<std::string> splitNames(const int size, const std::string names) {
    std::vector<std::string> split(size);
    std::string rest = names;
    for (int i = 0; i < size; ++i) {
        auto position = rest.find(",");
        split[i]      = rest.substr(0, position);
        rest          = rest.substr(position + 1, rest.size());
    }
    return split;
}

std::vector<std::vector<int>> splitDims(const int size, const std::string string) {
    std::vector<std::vector<int>> dims(size);
    std::string rest = string;
    for (int i = 0; i < size; ++i) {
        auto position = rest.find(",");
        dims[i]       = stringToDims(rest.substr(0, position), "x");
        rest          = rest.substr(position + 1, rest.size());
    }
    return dims;
}

ConfigFile::ConfigFile(std::string filename, std::string delimiter, std::string comment) : m_Delimiter(delimiter), m_Comment(comment) {
    // Construct a ConfigFile, getting keys and values from given file

    std::ifstream in(filename.c_str());
    if (in.fail()) {
        MNN_ERROR("Can't open %s\n", filename.c_str());
    }
    in >> (*this);
}

bool ConfigFile::KeyExists(const std::string& key) const {
    // Indicate whether key is found
    mapci p = m_Contents.find(key);
    return (p != m_Contents.end());
}

/* static */
void ConfigFile::Trim(std::string& inout_s) {
    // Remove leading and trailing whitespace
    static const char whitespace[] = " \n\t\v\r\f";
    inout_s.erase(0, inout_s.find_first_not_of(whitespace));
    inout_s.erase(inout_s.find_last_not_of(whitespace) + 1U);
}

std::ostream& operator<<(std::ostream& os, const ConfigFile& cf) {
    // Save a ConfigFile to os
    for (ConfigFile::mapci p = cf.m_Contents.begin(); p != cf.m_Contents.end(); ++p) {
        os << p->first << " " << cf.m_Delimiter << " ";
        os << p->second << std::endl;
    }
    return os;
}

void ConfigFile::Remove(const std::string& key) {
    // Remove key and its value
    m_Contents.erase(m_Contents.find(key));
    return;
}

std::istream& operator>>(std::istream& is, ConfigFile& cf) {
    // Load a ConfigFile from is
    // Read in keys and values, keeping internal whitespace
    typedef std::string::size_type pos;
    const std::string& delim = cf.m_Delimiter; // separator
    const std::string& comm  = cf.m_Comment;   // comment
    const pos skip      = delim.length(); // length of separator

    std::string nextline = ""; // might need to read ahead to see where value ends

    while (is || nextline.length() > 0) {
        // Read an entire line at a time
        std::string line;
        if (nextline.length() > 0) {
            line     = nextline; // we read ahead; use it now
            nextline = "";
        } else {
            std::getline(is, line);
        }

        // Ignore comments
        line = line.substr(0, line.find(comm));

        // Parse the line if it contains a delimiter
        pos delimPos = line.find(delim);
        if (delimPos < std::string::npos) {
            // Extract the key
            std::string key = line.substr(0, delimPos);
            line.replace(0, delimPos + skip, "");

            // See if value continues on the next line
            // Stop at blank line, next line with a key, end of stream,
            // or end of file sentry
            bool terminate = false;
            while (!terminate && is) {
                std::getline(is, nextline);
                terminate = true;

                std::string nlcopy = nextline;
                ConfigFile::Trim(nlcopy);
                if (nlcopy == "")
                    continue;

                nextline = nextline.substr(0, nextline.find(comm));
                if (nextline.find(delim) != std::string::npos)
                    continue;

                nlcopy = nextline;
                ConfigFile::Trim(nlcopy);
                if (nlcopy != "")
                    line += "\n";
                line += nextline;
                terminate = false;
            }

            // Store key and value
            ConfigFile::Trim(key);
            ConfigFile::Trim(line);
            cf.m_Contents[key] = line; // overwrites if key is repeated
        }
    }

    return is;
}
bool ConfigFile::FileExist(std::string filename) {
    bool exist = false;
    std::ifstream in(filename.c_str());
    if (in)
        exist = true;
    return exist;
}

void ConfigFile::ReadFile(std::string filename, std::string delimiter, std::string comment) {
    m_Delimiter = delimiter;
    m_Comment   = comment;
    std::ifstream in(filename.c_str());

    if (!in) {
        std::cout << "file is not existed!" << std::endl;
    }

    in >> (*this);
}
#endif // CONFIG_HPP